The Button letter was mailed on June 26th 1970 containing a footnote that stated "The map coupled with this code will tell you where the bomb is set. You have until next fall to dig it up". No bomb or any other relevant location was subsequently discovered. The Zodiac Killer's November 8th 1969 340 cipher remained "crackproof", the April 20th 1970 '13 Symbol' cipher was simply too short for any meaningful decryption, and by late July of 1970, this new '32 symbol' code and 'Phillips 66 Road Map' mailed on June 26th 1970 failed to provide little relief for an audience on the wane.

Probably realizing this, the Zodiac Killer issued his 'Little List' letter to the San Francisco Chronicle on July 26th 1970, just one month later. In this lengthy correspondence, the Zodiac Killer added two large crosshairs, likely to give us a hint regarding the design of the Button letter code. The first contained the number 13 on the east axis and a bold circle placed in the southwest quadrant accompanied by the acronym SFPD. This can be viewed on the left. The second crosshairs had "P.S. The Mt Diablo code concerns radians + inches along the radians" scrawled across its base. If we can decode their meaning, it may point us towards the area of interest "where the bomb is set". It is highly unlikely the Zodiac Killer ever buried a bomb, nevertheless, we can still unearth the intended threat.​

The Zodiac Killer referred to radians in the 'Little List' letter. An angle's measurement in radians is numerically equivalent to the length of a corresponding arc of a unit circle, with one radian measured at approximately 57.3 degrees. If we take a look at his placement of the bold zero next to SFPD on the 'Little List' letter, it lies well beyond the 180 degrees line, but before the 270 degrees line. If we now assume this was the area of interest or "where the bomb is set", it has to be 4 radians.5 radians = 286.5 degrees, so is too much.3 radians = 172 degrees, so is too small.Radians are usually measured counterclockwise, but if we look at the placement of the bold circle, it may indicate that Zodiac's intention was to to create an angle running clockwise, concurrent with magnetic north. ​

4 radians = 229 degrees, which is slightly shy of the positioning of the bold circle, that is, until we add back the magnetic north value from 1970, which was approximately 17 degrees off center to the right. Adding this to the 4 radians value of 229 degrees, we get 246 degrees. Now look at the image of the compass rose to the left. It matches exactly. Therefore, the bold circle that Zodiac drew, already incorporated the 17 degrees of magnetic north. This, is in all likelihood, the correct angle away from Mount Diablo. In other words, 4 radians + 17 degrees = 246 degrees.We now have the possible location of the bomb (or intended location) set clockwise of 'true north'. 246 degrees from Mount Diablo points towards the vicinity of Alameda and the Bayview area of San Francisco, but the bold circle could fall anywhere along this line. The only problem is scale. Due to the lack of pinpoint accuracy regarding the bold circle, only a rough location could ever be determined. So, until the 32 symbols on the Button letter are decoded, we are likely to wait yet another "fall to dig it up"..

Kevin Robert Brooks has recently released two videos on Youtube, outlining his case for Donald Lee Bujok as the man behind the mask, we only know as the Zodiac Killer. The first was outlined in the previous article: Thirteen Holes in Time. The second will be described here.

On June 26th 1970, the Zodiac Killer mailed the Button letter to the San Francisco Chronicle, upset that the citizens of San Francisco had not complied with his wishes to wear his Zodiac buttons, claiming he had killed a man in a parked car with a .38. He also designed a 32 symbol code - the fourth in a series of cryptic messages - of which only the first, the 408 Cipher was ever solved. Also accompanying the letter, was a Phillips 66 road map of San Francisco and Vicinity. On this map the Zodiac Killer had emblazoned his crosshairs symbol, centered over the peak of Mount Diablo, along with a brief segment of writing, stating it was to be set to Magnetic North.

The Zodiac Killer appeared a master of misdirection and false promises, placing the Bay Area into panic by proclaiming he would target a school bus and "pick off the kiddies as they came bouncing out". A threat that fortunately never materialized. His threat to use a bomb in several letters, including this Button letter, also appeared to carry little weight, other than to continue his campaign of terror using a pen, as opposed to a bullet.

Kevin Robert Brooks and his team of investigators believe they have found the real reason behind the Button letter and Phillips 66 Petroleum map of June 26th 1970 - and it is another classic case of Zodiac misdirection.

Donald Lee Bujok was born in Roundup, Musselshell County, Montana on July 6th 1936. Kevin Brooks believes the home address of the killer, namely Donald Lee Bujok, is the purpose behind the design of the Button letter and Phillips Petroleum map.Many serial killers collect trophies from their victims, often storing them for many years. Items were taken following the murder of Paul Stine in Presidio Heights on October 11th 1969 - and apart from the small sections of Paul Stine's shirt mailed to the San Francisco Chronicle on October 13th 1969, November 9th 1969, and attorney Melvin Belli's residence on December 20th 1969, the rest is unaccounted for. The innate desire to reveal one's identity and take credit for the crimes, is often counterbalanced with an equal desire to remain at liberty and continue the compunction to murder. This is the fine line some serial killers appear to tread - and undoubtedly the Zodiac Killer was no different.

The key to this mystery lies hidden in plain sight. In this instance, the clue lies in the map itself - a 1969 version of the Phillips 66 road map. The Phillips Petroleum Company (1917) was founded in Bartlesville, Oklahoma by brothers Frank and Lee Eldas Phillips, becoming an iconic American brand, the name in part, derived from testing undertaken on US Highway 66 in Oklahoma.

Kevin Robert Brooks takes us to the county seat of Roundup, Musselshell County, Montana where Donald Lee Bujok was born. This area of personal significance is where the Zodiac Killer was directing us all along. All we have to do now, is place the center of the Zodiac crosshairs over the area of Roundup, Musselshell County and follow the arrow placed at the top of the Zodiac crosshairs (set to Mag N,) and see where it takes us.The two immediate counties above Musselshell County, are Petroleum County (established in 1925) and Phillips County (established in 1915).

If we take the crossed circle and superimpose it over the center of Roundup, Montana, the directional North marker points directly to two adjacent counties. Firstly Petroleum County and secondly Phillips County, giving us the very real reason behind his choice of map in the first place, and the birth place of America's most elusive serial killer. On the Phillips 66 Petroleum map, the Zodiac Killer added a notation that his design "is to be set to Mag.N". Taken to be Magnetic North. In 1970, Magnetic North was approximately 16.5 degrees. If we adjust the crossed circle accordingly by 16.5 degrees, it becomes even more significant, with the directional marker passing exactly over both county seats of Winnett and Malta, shown on the map above.The county code numbers of Petroleum County and Phillips County are 55 and 11 respectively. These totaled up equal 66, to provide yet another interesting feature, bearing in mind the Phillips 66 map.Thanks again to Kevin Robert Brooks. ​

It has been widely considered that the Exorcist letter mailed on January 29th 1974 may have been the final correspondence from the infamous Zodiac Killer. But is its claim of 37 murders, if indeed this is what was meant, a realistic one.Firstly, we will take the unusual step of acknowledging the Zodiac Killer at his word, when throughout his campaign of terror he constantly informed the authorities of his murder count, displayed on each subsequent letter or card. But how accurate were his claims, and could a timeline of potential Zodiac victims be attributed to the periods in between each correspondence, bearing in mind that his declaration of seven murders on the Dripping Pen card of November 8th 1969 could be attributed with almost complete accuracy, albeit the missing murder in August, has still yet to be resolved.As stated previously, the months displayed at the foot of the Dripping Pen card could indicate the murder of David Faraday and Betty Lou Jensen in December, Darlene Ferrin in July, Cecelia Shepard in September, along with Paul Stine and Cheri Jo Bates in October. This meant six murders possibly attributed and one unaccounted for, due to his proclamation on November 8th 1969, indicating a total of seven victims up to this point.So let us examine the period from this letter to the next confirmed Zodiac correspondence on December 20th 1969, that of the Melvin Belli letter, claiming he may lose control and claim a ninth and tenth victim. The suggestion of a search for a ninth and tenth victim, by inference, meant he had already claimed his eighth murder victim and it must have occurred between November 8th 1969 and December 20th 1969. So who was the most likely Zodiac victim, based on age, locality and nature of the crime during this time period.One possibility is Betsy Aardsma, murdered in the campus library of Pennsylvania State University on November 28th 1969- although this crime has a number of question marks, including the locality- seemingly out of kilter with what we know of the killer to this point. There is, however, another interesting case that deserves closer scrutiny.

Leona LaRell Roberts (16), a resident of Napa, disappeared on December 10th 1969 from her boyfriend's apartment at 749 Tormey Avenue, Rodeo, feared kidnapped, after a neighbor recalled screams. Her nude body was eventually discovered on December 28th 1969 on a beach by Bolinas Lagoon, Marin County.Contra Costa County detectives found a 1963 Napa class ring on her finger- inscribed on the inner surface of the ring were the initials J.A.S. Although the cause of death was unclear, there was a suggestion of ligature marks on Leona Roberts wrists and ankles. According to Christopher J Farmer on his Opordanalytical article, a link to the Zodiac Killer was formulated with Gareth Penn being proposed as the prime suspect. Although this is an extremely well constructed article, with many interesting thoughts, it requires many leaps of faith to arrive at its conclusion- possibly too many to suggest this as a credible hypothesis.In this article he suggested a link between the Dragon Card and 3141 Paradise Drive, Tiburon as a possible burial site of Zodiac victims. This area is located 23 miles east of Bolinas Lagoon.

Elaine Davis

Incidentally, a woman's body was discovered next to Paradise Drive, Belvedere, Tiburon in December 1966, although the body, wearing a red dress had lain undiscovered for approximately three to four months, according to Marin County detectives.Also on December 1st 1969 Elaine Davis (17) disappeared from from her home in Walnut Creek, Contra Costa County, California. She was abducted during the evening hours through a sliding rear window. Two and a half weeks later on December 19th 1969 her body was discovered floating off Light House Point, Santa Cruz, California, however, due to investigators misinterpreting the age of the victim at the time, her identity was only realized 31 years later when officials exhumed the body in 2000.No link was ever ascertained between the murder of Elaine Davis and Leona Roberts, however, both victims fell within the correct age, area and timeline of the Zodiac Killer.

The Melvin Belli letter was mailed on the first anniversary of the Lake Herman Road double murder of David Faraday and Betty Lou Jensen on December 20th 1968. This correspondence was authenticated by the inclusion of a cut piece of Paul Stine's shirt, a taxicab driver callously gunned down in the Presidio on October 11th 1969.But what is interesting about the letter, is that it mentions a possible ninth and tenth victim- and bearing in mind three of his previous four attacks were on lone couples, the suggestion of a likely future double attack, would place Solano County deputies on high alert, with deserted lovers lane areas a priority for extra patrols. The threat in the Vallejo area, however, never materialized.On April 20th 1970, exactly four months later, the 'My Name is....Letter' landed on the doorstep of the San Francisco Chronicle. In this letter the Zodiac included a Bus Bomb Diagram, although more chillingly, was the declaration of 10 murders placed beside his now infamous crosshairs symbol. So who were his ninth and tenth victims.Exactly bisecting the dates of the Melvin Belli letter and the 'My Name is...Letter' were the murders of John Franklin Hood (24) and Sandra Garcia (20), brutally stabbed on a Santa Barbara beach on Saturday 21st February 1970. Had the Zodiac lost control as he had asserted in the Melvin Belli letter, with this double murder moving his victims count ominously forward to number 10.

On March 22nd Kathleen Johns was abducted and taken on a terrifying journey by an assailant she later claimed to be the Zodiac Killer. Even the Zodiac himself claimed his involvement, when he mailed a letter to the San Francisco Chronicle on July 24th 1970. There were many murders and disappearances in California during the month of March, including Cosette Ellison on March 3rd, Patricia King on March 5th, Judith Hakari on March 7th, Marie Anstey on March 13th and Eva Blau on March 20th. However, the 'My Name is...Letter' and Bus Bomb Diagram claimed 10 murders on April 20th 1970, with the Melvin Belli letter on December 20th 1969 indicating that 8 murders had taken place. If we therefore take the Zodiac at his word, only two murders had taken place in this four month period. If John Hood and Sandra Garcia were Zodiac victims, then none of the disappearances and murders in March were anything to do with the Zodiac Killer. On the other hand, if the Hood and Garcia murders were not Zodiac victims, then only two of these victims in March remain a possibility, not more. Unless for some reason only known to the killer, he committed more murders, yet failed to attribute them to himself.

Moving forward two months to the Button letter on June 26th 1970, the Zodiac claimed 12 murders. He also stated he had "shot a man sitting in a parked car with a .38".The only event that tallied with the Zodiac's claim was the murder of police officer Sgt Richard P. Radetich (25) on June 19th at 5.25 am, who was gunned down by three shots from a .38 caliber revolver at point blank range through the driver side window of his vehicle while in the process of serving a parking ticket. He was seated in his police car by 643 Waller Street, when it is believed another vehicle pulled alongside and an occupant opened fire. Officer Richard Radetich would die 15 hours later.However, the Zodiac Killer, who almost always gained extreme pleasure from his mockery towards the police and authorities, only referred to his victim in the Button letter as a 'man', apparently failing to capitalize on the situation.This appears to shed reasonable doubt that he was responsible for the murder of Sgt Richard Radetich, although the caliber of the weapon was correct. The disappearance of Donna Ann Lass (25) from the Sahara Tahoe Hotel on September 6th 1970 seemed to push the Zodiac's murder count to 13, with the Halloween card mailed on October 27th 1970 proclaiming a possible fourteenth victim, arriving just two days after the murder of Nancy Bennallack (27), a court reporter, on October 25th 1970.

Nancy Bennallack had been slain in her own apartment on Arden Way and Bell Avenue, Sacramento , cut down by over 30 knife wounds, indicating the severity of the brutal murder- although she had not been sexually assaulted. The crime scene indicated that the killer may have used tape to mask over his fingertips during the attack.Finally, onto the Los Angeles letter, mailed on March 13th 1971, where he laid claim to an estimated 17 or more murders.In this letter he stated "I do have to give them credit for stumbling across my riverside activity, but they are only finding the easy ones, there are a hell of a lot more down there".He was apparently referring to the fact that detectives had forged a link between the Zodiac Killer and the senseless slaying of Cheri Jo Bates in Riverside on October 30th 1966, claiming there were many more victims in that region.

One such attack, was the Robert Domingos (18) and Linda Edwards (17) double murder on June 4th 1963. The young couple were gunned down on a beach near Tajiguas Creek, Lompoc, Santa Barbara County.The killer had initially attempted to bind the couple, reminiscent of the Lake Berryessa Attack on Bryan Hartnell and Cecelia Shepard on September 27th 1969. But clearly, if the Zodiac was responsible for this couple's murder, along with Cheri Jo Bates, then his murder total should have read 8, by the mailing of the Dripping Pen card on November 8th 1969, which clearly it didn't. The suggestion of "there are a hell of a lot more down there", seems to conflict with his declaration on the Dripping Pen card of seven murders. The only reasonable explanation being, that these murders were not committed under the Zodiac umbrella. A pseudonym he would only adopt just prior to the 'Debut of Zodiac' letter, received by the San Francisco Examiner on August 4th 1969. The killer may have belatedly attached the 1963 murders of Domingos and Edwards, and the Riverside murder of Cheri Jo Bate to the Los Angeles letter claiming 17+ murders. This may explain the increase from the 14 victims claimed in the Halloween card approximately five months earlier.